Ignition Timing Inspection

Connect the Honda Diagnostic System (HDS) to the data link connector (DLC).
- K24Z1 engine (see HOW TO USE THE HDS (HONDA DIAGNOSTIC SYSTEM) )
- K24Z6 engine (see HOW TO USE THE HDS (HONDA DIAGNOSTIC SYSTEM) )
Turn the ignition switch to ON (II).
Make sure the HDS communicates with the vehicle and the powertrain control module (PCM). If it doesn't communicate, troubleshoot the DLC circuit.
- K24Z1 engine (see DLC CIRCUIT TROUBLESHOOTING )
- K24Z6 engine (see DLC CIRCUIT TROUBLESHOOTING )
Start the engine. Hold the engine speed at 3, 000 rpm without load (in P or N) until the radiator fan comes on, then let it idle.
Check the idle speed.
- K24Z1 engine (see IDLE SPEED INSPECTION )
- K24Z6 engine (see IDLE SPEED INSPECTION )
Jump the SCS line with the HDS.
Connect the timing light to the service loop (white tape).

Fig 1: Checking Idle Speed Using Timing Light
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Aim the light toward the pointer (A) on the cam chain case. Check the ignition timing under a no load condition (headlights, blower fan, rear window defogger, and air conditioner are turned off).
Ignition Timing:

8±2° BTDC (RED mark (B)) at idle in P or N

Fig 2: Identifying Pointer On Cam Chain Case
Courtesy of AMERICAN HONDA MOTOR CO., INC.
If the ignition timing differs from the specification, check the cam timing. If the cam timing is OK, update the PCM, if it does not have the latest software, K24Z1 engine (see PCM UPDATE ), K24Z6 engine (see PCM UPDATE ), or substitute a known-good PCM, K24Z1 engine (see SUBSTITUTING THE PCM ), K24Z6 engine (see SUBSTITUTING THE PCM ), then recheck. If the system works properly, and the PCM was substituted, replace the original PCM, K24Z1 engine (see PCM REPLACEMENT ), K24Z6 engine (see PCM REPLACEMENT ).
Disconnect the HDS and the timing light.